Scilab Function
Last update : April 2000

drawaxis - draw an axis

### Calling Sequence

  `drawaxis([options])`
  `// options: x,y,dir,sub_int,fontsize,format_n,seg,textcolor,ticscolor,tics`

### Parameters

- `dir=string`: used to specify the tics direction. `string` can be chosen among 'u','r','d','l' and 'l' is the default value. the values 'u','r','d','l' stands respectively for up, right, down, left
- `tics=string`: A flag which describes how the tics are given. `string` can be chosen among 'v','r', and 'i', and, 'v' is the default value
- `x,y`: two vectors which give tics positions.
- `val= string matrix`: A string matrix, which, when given, gives the string to be drawn along the axis at tics positions.
- `fontsize=int`: specifies the fontsize to use for displaying values along the axis. Default value is `-1` which stands for current fontsize
- `format_n=string`: format to use for displaying numbers along the axis
- `seg= 1 or 0`: A flag which controls the display of the base segment of the axis (default value is 1).
- `sub_int=integer`: an integer which gives the number of sub-intervals to draw between large tics.
- `textcolor=integer`: specify the color to use for displaying values along the axis. Default value is `-1` which stands for current color.
- `ticscolor=integer`: specify the color to use for tics drawing. Default value is `-1` which stands for current color.

### Description

`drawaxis` is used to draw an axis in vertical or horizontal direction. the direction of the axis is given by dir `dir = 'u'` or `'d'` gives a horizontal axis with tics going up (`'u'`) or down (`'d'`). `dir = 'r'` or `'l'` give a vertical axis with tics going right (`'r'`) or left (`'l'`).

`x` and `y` give the axis tics positions. If the axis is horizontal then `y` must be a scalar or can be omitted and `x` is a Scilab vector. The meaning of `x` is controlled by `tics`.

If `tics='v'` then `x` gives the tics positions along the x-axis.

If `tics='r'` then `x` must be of size 3. `x=[xmin,xmax,n]` and `n` gives the number of intervals.

If `tics='i'` then `x` must be of size 4, `x=[k1,k2,a,n]`. then `xmin=k1*10^a`, `xmax=k2*10^a` and `n` gives the number of intervals

If `y` is omitted then the axis will be positioned at the top of the frame if `dir='u'` or at the bottom if `dir='d'`

By default, numbers are drawn along the axis. They are drawn using a default format which can be changed with `format_n`. It is also possible to display given strings and not numbers, this is done if `val` is provided. The size of `val` must match the number of tics.

### Examples

    plot2d(1:10,1:10,1,"020")
    // horizontal axis
    drawaxis(x=2:7,y=4,dir='u',tics='v')
    // horizontal axis on top of the frame
    drawaxis(x=2:7,dir='u',tics='v')
    // horizontal axis at the bottom of the frame
    drawaxis(x=2:7,dir='d',tics='v')

    // horizontal axis given by a range
    drawaxis(x=[2,7,3],y=4,dir='d',tics='r')

    // vertical axis
    drawaxis(x=4,y=2:7,dir='r',tics='v')
    drawaxis(x=2,y=[2,7,3],dir='l',tics='r')
    drawaxis(y=2:7,dir='r',tics='v')
    drawaxis(y=2:7,dir='l',tics='v')

    // horizontal axis with strings displayed at tics positions
    drawaxis(x=2:7,y=8,dir='u',tics='v',val='A'+string(1:6));
    // vertical axis with strings displayed at tics positions
    drawaxis(x=8,y=2:7,dir='r',tics='v',val='B'+string(1:6));

    // horizontal axis given with a 'i' range.
    drawaxis(x=[2,5,0,3],y=9,dir='u',tics='i');
    drawaxis(x=9,y=[2,5,0,3],dir='r',tics='i',sub_int=5);

    // horizontal axis again
    drawaxis(x=2:7,y=4,dir='u',tics='v',fontsize=10,textcolor=9,ticscolor=7,seg=0,sub_int=20)

### Author

J.Ph.C.